import math
def chu_vi_hinh_vuong(n):
    """Tinh chu vi hinh vuong co chieu dai moi canh la n
    su dung cong thuc n*4    
    """
    return n*4

def dien_tich_hinh_vuong(n):
    """Tinh dien tich hinh vuong co chieu dai moi canh la n
    su dung cong thuc n^2   
    """
    return n**2

def chu_vi_hinh_chu_nhat(m,n):
    """Tinh chu vi hinh chu nhat co chieu dai va chieu rong la m, n
    Su dung cong thuc (m+n)*2
    """
    return (m+n)*2

def dien_tich_hinh_chu_nhat(m,n):
    """Tinh chu vi hinh chu nhat co chieu dai va chieu rong la m, n
    Su dung cong thuc (m+n)*2
    """
    return m*n

def chu_vi_hinh_tron(r):
    """Tinh chu vi hinh trong co ban kinh r 
    su dung cong thuc toan hoc 2*pi*r
    """
    return math.pi*r*2

def dien_tich_hinh_tron(r):
    """Tinh chu vi hinh trong co ban kinh r 
    su dung cong thuc toan hoc pi*r^2
    """
    return math.pi*r**2


